Method of die casting



Aug. 19, 1969 G. NYsr-:Llus

METHOD! oF DIE CASTING Filed Sept. 14.v 1966 INI/mm2 T /i f/ NLNN UnitedStates Patent ice l 3,461,946 Patented Aug. 19, 1969 3,461,946 METHOD OFDIE CASTING Gustav Nyselius, Stamford, Conn., assignor, by mesneassignments, to Vasco Metals Corporation, Latrobe, Pa., a corporation ofPennsylvania Filed Sept. 14, 1966, Ser. No. 579,265 Int. Cl. B22d 17/04,35/ 00 U.S. Cl. 164-113 2 Claims ABSTRACT OF THE DISCLOSURE Thisinvention relates to die casting of metals and par- -ticularly to asystem for automatically supplying molten metal from a heated la=under,or supply conduit, to one or more die casting machines, preferably to abattery of casting machines, of the kind in which a piston isreciprocated within a charging sleeve, t-o force a charge into a diecavity.

An object of the invention is to automatically refill the chargingsleeve with molten metal, without any manual operation, as ysoon as itis emptied, or partly emptied, by the charging stroke of the piston andthe piston has been retracted.

Another object of the invention is to reduce to a minimum the amount -ofslag by eliminating any runner and feeding as directly as possible fromthe charging sleeve to the gate of the die cavity and thus reducing thevolume of molten metal required for each charge and reducing thev sizeof charging sleeve that is required.

Another object of the invention is to save the -time heretofore requiredin ladling molten metal into a charging sleeve or any other manualoperation heretofore employed to actuate a lever or turn a valve forcausing molten metal to be supplied into a charging sleeve.

Another object of the invention is -to eliminate the enlarged portionsof a launder lor molten metal supply conduit heretofore employed tohouse goosenecks conventially used as the charging sleeves in thecasting of zinc and thus conserve floor space.

Another object of the invention is to increase the efliciency of diecasting by saving space and the operators time, and by decreasing waste,and increasing the number of castings produced per unit of time.

The invention will best be understood by reading the followingdescription in connection with the drawings, in which:

FIGURE l is a top plan view of a system embodying the invention,

FIGURE 2 is an end cross sectional view taken on the lines 2 2 of'FIGURE 1, and

FIGURE 3 is a side elevation partly in cross section taken on the lines3-3 of FIGURE l.

As shown herein the molten -metal to be cast is supplied automatically,by gravity, Ifrom within a range of levels ina launder, to a heatedcharging sleeve which has an outlet port leading from the top -orhighest part of the sleeve to a gate defined between opposed die plates.It will be noted that the launder is of a uniform diameter and is not4widened at intervals to provide a succession of spaces each adapted 'toreceive a gooseneck charging sleeve, such for example as Ais shown inU.S. Patent 2,799,066. Where a number of die casting machines are beingsupplied-from a common launder the provision of enlarged areas ytoreceive gooseneck charging sleeves substantially decreases the floorspace and thus decreases the number of diecasting machines which can beemployed within a given area.

In'FIGURE 1 a launder 10 of uniform diameter is shown which is supplied-with molten metal from a furnace not shown. From the launder 10 branchconduits 12 and 14 lead to,the inlet ports 16 and 18 .respectively ofthe chargin-g sleeves 20 and 22 of a pluralitv of die casting machines,which may be conventional apart from the parts illustratedherein. Sincethe means for reciprocating the pistons 24 and 26 within sleeves 20 and22 respectively may be conventional it is not necessary to show ordescribe it herein. The inlet ports 16 and 18 are located in advance ofthe position of pistons 24 and 26 respectively when fully retracted.

As shown herein the charging sleeves 20 and 22 are dispose-dhorizontally, the -forward ends of the sleeves are closed, and theoutlet ports are in the yform of short nipples 28 -and 130 which arerespectively aligned with the planes. of the parting line between thesets of die plates 32, v'34 and 36, 38 and communicate respectively withthe gates 40 and 42, defined between the opposed faces of the pairs ofydie plates, which in turn communicate with the die cavities 44 and 46which are also defined between the faces of the opposed pairs of dieplates. The sleeves 20 and l22 and Atheir discharge port nipples 28 and30 respectively are heated, as by the electric heating coils c.

It will be noted that the level of the molten metal m within the launder10 is preferably above the top of the sleeves 20 and 22, and s-o thesleeves will be completely refilled with molten metal, automatically, bygravity, immediately after each reciprocation of the charging pistons,and that the level of the molten metal m within the launder is `belowthe top of the discharge port nipples 28 and 30 and that therefore thesleeves cannot overflow, with lspillage yfrom the nipples, as forexample when the pairs of die plates are separated and the communicationof the nipples `with the gates 40 and 42 is thus broken.

With the structure described above no manual operation is required inconnection with lling the charging sleeves and the resulting saving oftime makes possible an increase in production of castings -since thetime required per casting cycle is accordingly reduced.

While the invention is not limited to the casting of any particularmetal nor primarily concerned with the material used for the castingsleeve, if sleeves made of steel are employed the invention isparticularly useful for casting Zinc and other metals having a meltingpoint below the temperature continual exposure .to which is damaging tosteel. Obviously -aluminum and other metals having a higher meltingpoint .may be automatically charged into, and allowed to stand in,sleeves made of material impervious to the higher temperatures.

There has thus been provided apparatus land method by the use of whichthe above stated objects are realized in a thoroughly Ipractical way.

What I claim is:

1. The method of casting metals in a die cavity delined between opposeddie plates and having a gate also defined between said die plates, whichcomprises, supplying molten metal to said gate from a heated outletnipple located on the top of a heated charging sleeve havingreciprocable means therein for forcing molten metal from within thesleeve through said gate into said die cavity, andvautomaticallyrefilling the sleeve when the reciprocable means is retracted from asupply of molten metal the -level of which is below the top of saidnipple and above the top of the interior of Isaid charging sleeve.

2. The method of casting metals which comprises, providing a die cavitydened 'between opposed die vplates and having a gate also definedbetween said die plates, providing a charging sleeve with an outletnipple disposed directly below said gate in alignment with said gate,and with reciprocable means therein for forcing molten metal from withinthe sleeve through said gate into said die cavity, maintaining theliquid level within the launder conduit between the level of thelinterior of the sleeve at the top and the level of the discharge end ofthe nipple, and automatically refilling the sleeve when the reciprocablemeans is retracted, from a supply of molten metal the level of which is`below the top of said nipple and above the top of the interior of saidcharging sleeve.

References Cited UNITED STATES PATENTS 3/1940 Daesen 164-113 11/1961Rearwin 164-309 X 6/1965 Le Jeune 164-309 8/1965 Nyselius 164-312 U.S.Cl. X.R.

